RDMA: During rereg_mr ensure that REREG_ACCESS is compatible

If IB_MR_REREG_ACCESS changes from RO to RW then the umem has to be
re-evaluated to ensure it is properly pinned as RW. Since the umem is
hidden inside each driver's mr struct add a ib_umem_check_rereg() function
that each driver has to call before processing IB_MR_REREG_ACCESS.

mlx4 has to retain its duplicate ib_access_writable check because it
implements IB_MR_REREG_ACCESS | IB_MR_REREG_TRANS by changing both items
in place sequentially while the MR is live, so it will continue to not
support this combination.

Cc: stable@vger.kernel.org
Fixes: b40656aa7d55 ("RDMA/umem: remove FOLL_FORCE usage")
Link: https://patch.msgid.link/r/0-v1-06fb1a2d6cf5+107-rereg_access_jgg@nvidia.com
Reported-by: Philip Tsukerman <philiptsukerman@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c
index 786fa1aa8e552bfbb87f87b3f1e390a767d17406..4b055712b0d0db5fab6b55541fea6b8a4165c0ae 100644 (file)
--- a/drivers/infiniband/core/umem.c
+++ b/drivers/infiniband/core/umem.c
@@ -332,3 +332,19 @@ int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
                return 0;
 }
 EXPORT_SYMBOL(ib_umem_copy_from);
+
+/*
+ * Called during rereg mr if the driver is able to re-use a umem for
+ * IB_MR_REREG_ACCESS.
+ */
+int ib_umem_check_rereg(struct ib_umem *umem, int flags, int new_access_flags)
+{
+       if (!umem)
+               return 0;
+
+       if ((flags & IB_MR_REREG_ACCESS) && !(flags & IB_MR_REREG_TRANS))
+               if (ib_access_writable(new_access_flags) && !umem->writable)
+                       return -EACCES;
+       return 0;
+}
+EXPORT_SYMBOL(ib_umem_check_rereg);

diff --git a/drivers/infiniband/hw/hns/hns_roce_mr.c b/drivers/infiniband/hw/hns/hns_roce_mr.c
index 896af1828a38de67bccb4c7295aa836637297a12..25bfd3970f5b6e332144cf4773436206197ac0f2 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_mr.c
+++ b/drivers/infiniband/hw/hns/hns_roce_mr.c
@@ -300,6 +300,10 @@ struct ib_mr *hns_roce_rereg_user_mr(struct ib_mr *ibmr, int flags, u64 start,
                goto err_out;
        }
 
+       ret = ib_umem_check_rereg(mr->pbl_mtr.umem, flags, mr_access_flags);
+       if (ret)
+               goto err_out;
+
        mailbox = hns_roce_alloc_cmd_mailbox(hr_dev);
        ret = PTR_ERR_OR_ZERO(mailbox);
        if (ret)

diff --git a/drivers/infiniband/hw/irdma/verbs.c b/drivers/infiniband/hw/irdma/verbs.c
index 17086048d2d7fc2fae29378d514abdc5b4c710bd..8cd4275328052e9f5f5bffaea6eed488540e2791 100644 (file)
--- a/drivers/infiniband/hw/irdma/verbs.c
+++ b/drivers/infiniband/hw/irdma/verbs.c
@@ -3803,6 +3803,10 @@ static struct ib_mr *irdma_rereg_user_mr(struct ib_mr *ib_mr, int flags,
        if (flags & ~(IB_MR_REREG_TRANS | IB_MR_REREG_PD | IB_MR_REREG_ACCESS))
                return ERR_PTR(-EOPNOTSUPP);
 
+       ret = ib_umem_check_rereg(iwmr->region, flags, new_access);
+       if (ret)
+               return ERR_PTR(ret);
+
        if (dmabuf_revocable) {
                umem_dmabuf = to_ib_umem_dmabuf(iwmr->region);
 

diff --git a/drivers/infiniband/hw/mlx4/mr.c b/drivers/infiniband/hw/mlx4/mr.c
index 650b4a9121ff6d6e149eb16217f9dd7b57907094..6747bca3067770ad0a763dc5087ac74bdd8c9dcb 100644 (file)
--- a/drivers/infiniband/hw/mlx4/mr.c
+++ b/drivers/infiniband/hw/mlx4/mr.c
@@ -209,6 +209,10 @@ struct ib_mr *mlx4_ib_rereg_user_mr(struct ib_mr *mr, int flags, u64 start,
        struct mlx4_mpt_entry **pmpt_entry = &mpt_entry;
        int err;
 
+       err = ib_umem_check_rereg(mmr->umem, flags, mr_access_flags);
+       if (err)
+               return ERR_PTR(err);
+
        /* Since we synchronize this call and mlx4_ib_dereg_mr via uverbs,
         * we assume that the calls can't run concurrently. Otherwise, a
         * race exists.

diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c
index 3b6da45061a55278b0e5d1b0e4a4eb89f2c75367..fb40b44496f47a0c8c2c1076031a67267bc61d34 100644 (file)
--- a/drivers/infiniband/hw/mlx5/mr.c
+++ b/drivers/infiniband/hw/mlx5/mr.c
@@ -1179,6 +1179,10 @@ struct ib_mr *mlx5_ib_rereg_user_mr(struct ib_mr *ib_mr, int flags, u64 start,
        if (flags & ~(IB_MR_REREG_TRANS | IB_MR_REREG_PD | IB_MR_REREG_ACCESS))
                return ERR_PTR(-EOPNOTSUPP);
 
+       err = ib_umem_check_rereg(mr->umem, flags, new_access_flags);
+       if (err)
+               return ERR_PTR(err);
+
        if (!(flags & IB_MR_REREG_ACCESS))
                new_access_flags = mr->access_flags;
        if (!(flags & IB_MR_REREG_PD))

diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.c b/drivers/infiniband/sw/rxe/rxe_verbs.c
index 4d4891dc28846b38575a4cb0588a5ac939808031..4cf04a44189c64e447af701a30715c57d2ac4304 100644 (file)
--- a/drivers/infiniband/sw/rxe/rxe_verbs.c
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.c
@@ -1319,6 +1319,7 @@ static struct ib_mr *rxe_rereg_user_mr(struct ib_mr *ibmr, int flags,
        struct rxe_mr *mr = to_rmr(ibmr);
        struct rxe_pd *old_pd = to_rpd(ibmr->pd);
        struct rxe_pd *pd = to_rpd(ibpd);
+       int err;
 
        /* for now only support the two easy cases:
         * rereg_pd and rereg_access
@@ -1328,6 +1329,10 @@ static struct ib_mr *rxe_rereg_user_mr(struct ib_mr *ibmr, int flags,
                return ERR_PTR(-EOPNOTSUPP);
        }
 
+       err = ib_umem_check_rereg(mr->umem, flags, access);
+       if (err)
+               return ERR_PTR(err);
+
        if (flags & IB_MR_REREG_PD) {
                rxe_put(old_pd);
                rxe_get(pd);

diff --git a/include/rdma/ib_umem.h b/include/rdma/ib_umem.h
index 2ad52cc1d52bdd910a5a2d87c29ce5944ae6d12b..49172098a8de1436a847c1c1532b630753cb3615 100644 (file)
--- a/include/rdma/ib_umem.h
+++ b/include/rdma/ib_umem.h
@@ -156,6 +156,8 @@ void ib_umem_dmabuf_revoke_lock(struct ib_umem_dmabuf *umem_dmabuf);
 void ib_umem_dmabuf_revoke_unlock(struct ib_umem_dmabuf *umem_dmabuf);
 void ib_umem_dmabuf_revoke(struct ib_umem_dmabuf *umem_dmabuf);
 
+int ib_umem_check_rereg(struct ib_umem *umem, int flags, int new_access_flags);
+
 #else /* CONFIG_INFINIBAND_USER_MEM */
 
 #include <linux/err.h>
@@ -230,5 +232,11 @@ static inline void ib_umem_dmabuf_revoke_lock(struct ib_umem_dmabuf *umem_dmabuf
 static inline void ib_umem_dmabuf_revoke_unlock(struct ib_umem_dmabuf *umem_dmabuf) {}
 static inline void ib_umem_dmabuf_revoke(struct ib_umem_dmabuf *umem_dmabuf) {}
 
+static inline int ib_umem_check_rereg(struct ib_umem *umem, int flags,
+                                     int new_access_flags)
+{
+       return -EOPNOTSUPP;
+}
+
 #endif /* CONFIG_INFINIBAND_USER_MEM */
 #endif /* IB_UMEM_H */